An illumination device installed in proximity to the eyes of people such as a pendant light is important in how it appears when it is turned off. For example, in order to avoid closed atmosphere in a room, it is desired to provide an illumination device which appears to be transparent when it is turned off. An example of such illumination device includes a device using a transparent light-guiding plate that guides light emitted by an LED light source and that diffuses the light with a scatter pattern to output the light to the outside through a light output surface. In this case, there is much component of light that is not diffused by the scatter pattern and that is guided to an end portion far from the LED light source.
Therefore, there is an illumination device that uses a member such as a reflection sheet that reflects, toward a light output surface, the light which has reached the end portion of a light-guiding body. However, it used to be impossible to efficiently output, through the light outputs surface, the light that has reached the end portion of the light-guiding plate without deteriorating the transparentness of the illumination device.